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Growing interest in virtual reality (VR) and its technical development has resulted in several applications for training and teaching purposes. This paper studied an immersive VR platform, hereafter referred to as IVR, developed for training in motor-manual tree delimbing as a learning tool, which is one of the first in forestry work training. The tested platform was the Husqvarna Limberjack, available for free download and publicly accessible. The platform uses an immersive VR to teach users how to delimb stems with a chainsaw. The study included four groups with different previous experience of using immersive VR as the first factor and a chainsaw as the second factor. The experiment included records of the time required to complete the tasks. That data was used in a procedural study in which the average and best times of the groups were utilized. Statistical analysis showed differences between the groups with and without experience in both factors. The learning curves showed a 12.4 to 26.7% improvement for all four groups. The IVR platform turned out to be a useful training aid, where skills can be gained before going to practice in field. [ABSTRACT FROM AUTHOR]

Monitoring of operations has become a critical activity in forestry, aiming to provide the data required by planning and production management. Conventional methods, on the other hand, come at a high expense of resources. A neural network was trained, validated, and tested in this study based on multi-modal data to classify relevant operational events in mechanized weed control operations. The architecture of a neural network was tuned in terms of the number of hidden layers and neurons, and the regularization term was set at various values to obtain optimally tuned models for three data modalities: triaxial acceleration data coupled with speed extracted from GNSS signals (AS), triaxial acceleration (A), and speed alone (S). In the training and validation phase, the models based on AS and A achieved a very high classification accuracy, accounting for 92 to 93% when considering four relevant events. In the testing phase, which was run on unseen data, the classification accuracy reached figures of 91 to 92%, indicating a good generalization ability of the models. The results point out that multimodal data are able to provide the features for distinguishing events and add spatial context to the monitored operations, standing as a suitable solution for offline, partly automated monitoring. Future studies are required to see how the capabilities of online, real-time technologies such as deep learning coupled with computer vision can add more context and improve classification performance. [ABSTRACT FROM AUTHOR]

The performance of timber harvesting equipment is important for local operational planning and for making decisions on the way in which the forests should be opened up. However, there are many options used to extract timber, and there is a high variability in their performance. Forwarding is commonly used and became an attractive option for low-access forests. A controlled experiment was set up in this study to see how the configuration of the trails, characterized in terms of slope and surface condition, and the extraction direction (uphill or downhill) may affect the performance of forwarding operations. GNSS (Global Navigation Satellite System) data were collected at a rate of 5 s for five replications of moving empty downhill and uphill, respectively, on a dirt trail, measuring 250 m in length and having a slope of about 11%. The same experiment was run with the machine loaded at full capacity, then four replications with the machine loaded and unloaded moving downhill and uphill, respectively, were performed on a forest road resembling a rocky trail, which measured 390 in length and had a slope of about 4%. GNSS data were used to extract the moving speed for all the tested conditions with the aim to compute the cycle time, and the payload volume estimate was used to estimate efficiency, and productivity, depending on extraction distance in a range of 50 to 1000 m. For the first trail, statistical comparison tests indicated significant differences in the speed of uphill and downhill movement, for both empty and loaded conditions, whereas for the second trail, there were no significant differences in speed. In addition, on the second trail, the sustained speed was almost double. These were reflected sharply in the cycle time, efficiency, and productivity, depending on extraction distance and trail condition. These findings are important for decision making on local operational planning and forest opening up. [ABSTRACT FROM AUTHOR]

Wildfires present a major global environmental issue, exacerbated by climate change. The Iranian Northern Zagros Forests, characterized by a Mediterranean climate, are particularly vulnerable to fires during hot, dry summers. This study investigates the impact of climate change on forest fires in these forests from 2006 to 2023. The analysis revealed significant year-to-year fluctuations, with notable fire occurrence in years 2007, 2010, 2021, and 2023. The largest burned area occurred in 2021, covering 2655.66 ha, while 2006 had the smallest burned area of 175.27 ha. Climate variables such as temperature, humidity, precipitation, wind speed, heat waves, and solar radiation were assessed for their effects on fire behavior. Strong correlations were found between higher average temperatures and larger burned areas, as well as between heat waves and increased fire frequency. Additionally, higher wind speeds were linked to larger burned areas, suggesting that increased wind speeds may enhance fire spread. Multiple linear regression models demonstrated high predictive accuracy, explaining 84% of the variance in burned areas and 69.6% in the variance in fire frequency. These findings document the growing wildfire risk in the Northern Zagros region due to climate change, highlighting the urgent need to integrate scientific research with policies to develop effective wildfire management strategies for sustainable forest management. [ABSTRACT FROM AUTHOR]

Farm tractors represent a possible option for forwarding operations in continuous cover forestry, given the generally lower removal intensities, relatively high dispersion of timber, and heightened concerns regarding the environmental impact of operations. This study evaluated the performance of a farm tractor fitted with an externally operated crane and a bunk for forwarding operations, using field-documented data on operational speed, production, and fuel use, as well as data from high-resolution video recordings for a detailed time-and-motion study. Using this knowledge, performance simulations were run based on extraction distance and log size, to describe the variability in fuel use, cycle time, and productivity, and to estimate the operational cost. The results of the simulation showed important differences in operational speed across different work elements, involving machine movement. Although the extraction distance had effects, log size was found as the important factor driving the variability in cycle time, productivity, fuel use, and cost. The differences in performance based on the variability in extraction distance and log size may serve as a guideline for operational planning, costing, and environmental assessment regarding emissions under various operating conditions. [ABSTRACT FROM AUTHOR]

Featured Application: Penetration resistance is a descriptor of soil compaction. In this study, we have exercised control over the weight of the payload of three timber extraction options, therefore the results may be used to estimate the contribution to soil compaction of each pass, as well as for comparison and for planning of operations, given the trends and the magnitude of penetration resistance between the passes. Local effects of ground-based timber harvesting, such as soil compaction, are often important for forest management and resilience of forests. One way to evaluate the compaction of the forest soils is by the penetration resistance. Most often, however, the control over the weight of the means used to extract the wood is difficult to maintain, influencing therefore the outcomes of the comparison studies. In this study, a controlled experiment was set up to see how the penetration resistance is affected by the number of passes of three wood extraction methods. A first objective of the study was to characterize the undisturbed soils by the mean values of penetration resistance along the profile. The second objective of the study was to compare the changes in penetration resistance induced by the number of passes along the soil profile. The extraction means were selected based on their typical use in flat-land operations, namely horse logging, skidding and forwarding, and the weight of their loads was determined before the experiment; then, each one was tested in a different area by operating in a closed loop on flat land, with 15 passes over the respective testing area. Penetration resistance was sampled up to 80 cm in depth in 10 control points, as well as in 10 sampling points over the wheels' footprints. Ten samples were taken on the latter after the first, second, third, fourth, fifth, tenth and fifteenth passes, and comparisons were set up based on natural changing points in penetration resistance found in the control areas. The comparisons found significant differences by an increase in penetration resistance for all three extraction means, and there was a difference by an order of magnitude and depth; horse logging affected it the least and forwarding the most in magnitude, while skidding seemed to produce more significant changes in depth. However, the magnitude and depth of these changes may have depended on the characteristics of the soils from the test areas, and it cannot be concluded that the found levels of penetration resistance will affect the trees located nearby the experimental trails. The problem of soil compaction should be further examined by dedicated studies, given the variability in soil characteristics and diversity in means used to extract timber. [ABSTRACT FROM AUTHOR]

This year, the Technodiversity project comes at the end of its implementation. Besides the dedicated e-learning platform, and Technodiversity booklet, one of the important results of the project was the production of scientific audio-visuals aimed at exemplifying and explaining the main sub-processes relevant to forest operations, in a harmonized way of presentation. The project consortium has succeeded to produce a number of 47 high-quality-media scientific audio-visuals, accounting for a total duration of close to 5.4 hours. These files cover the main description of the processes by a functiogram, the typical work cycle as of the depicted sub-process, and an audio-visual representation of the action in each sub-process by integrating video, media and voice components. A full list of the audio-visuals is available for watching on the YouTube, covering, among others, operations carried out with chainsaws, fellers, processors, harvesters, chippers, horse logging, farm tractors, cable skidders, grapple skidders, clambunk skidders, forwarders, sledge yarders, tower yarders, and processor tower yarders. The duration of the produced audio-visuals ranges from 3:59 to 11:19 minutes, averaging 6:52 minutes. This work presents the rationale behind the development, materials and methods used in their development, and the structure of audio-visuals. [ABSTRACT FROM AUTHOR]

This study was set up to find out how Finnish timber transport entrepreneurs perceive their operating environment in terms of using larger and heavier vehicles (LHVs and HCVs), with the main aim of providing guidance for developing sustainable policies that would improve timber transportation. A total of 100 entrepreneurs responded to a questionnaire survey which contained three sections administrated by an online service. Five-point Likert scales were used to collect perceptions and, in addition to statistical descriptors, the Kruskal Wallis and Mann-Whitney U test was used to compare the responses of entrepreneurs. They felt that the 76 t vehicle combination is best suited for transporting timber when transport starts from the forest. When the analysis considered transport from terminals, 76 t combinations remained the most popular, but the popularity of >76 t combinations increased substantially. The farther the LHVs operate from the highways, the less suitable the road network was perceived for timber transport. The results also show that driving and rest time regulations as parts of the working time legislation were perceived as the most disruptive. Further, the availability, responsiveness of technical support, and long delays in solving the queries of drivers were critical problems for the efficient use of in-vehicle ICTapplications. The profitability over the 2014–2018 period has declined more for entrepreneurs using <76 t vehicle combinations. When looking at the development of profitability over the 2020–2024 period, the responses changed in a more positive direction. However, the current skilled workers are retiring and there are too few educated ones to replace them. This is expected to increase wages, which may be reflected in a decreased profitability in the timber transport sector in the future. [ABSTRACT FROM AUTHOR]

Fine-grained soils cause problems for forest road construction and often require improvements of their mechanical properties. One of the methods of improving mechanical properties of clay soils is soil stabilization. In this study, the effect of a conventional (lime) and a non-conventional (sodium nanoalginate) stabilizer on improving the characteristics of a high plasticity forest soil was compared. Atterberg limits including liquid limit, plastic limit and plasticity index, standard Proctor, UCS (Unconfined Compression Strength) and CBR (California Bearing Ratio) tests were performed on control (untreated) and soil samples treated with different doses (3%, 5% and 7%) of lime and sodium nanoalginate, according to the standard procedures. Moreover, to evaluate the effect of curing time, additional tests were performed on the soil samples treated with 3% lime and 3% sodium nanoalginate at 7, 14 and 28 days after the treatment. The results indicated that adding sodium nanoalginate and lime to the forest soil improves the Atterberg limits. Additionally, adding sodium nanoalginate to the forest soil increases the maximum dry density (γdmax) and decreases the optimum moisture content (OMC), whereas adding lime to the forest soil reduces the maximum dry density and increases the optimum moisture content. Adding sodium nanoalginate and lime in different doses (3%, 5% and 7%) increased UCS and CBR as the main indices of soil strength. The increment range of UCS for the soil stabilized with sodium nanoalginate and lime was 42.59%–160.14% and 31.34%–56.65%, respectively, and the range of CBR improvement for soil stabilized with sodium nanoalginate and lime was 28.72%–122.97% and 13.83%–45.59%, respectively. Increasing the curing time improved the mechanical properties of the forest soil in the samples treated with both stabilizers, but sodium nanoalginate performed better in soil stabilization. [ABSTRACT FROM AUTHOR]

Îmbunătăţirea şi menţinerea performanţei academice necesită resurse importante, mai ales într-un context naţional şi internaţional foarte competitiv cum este cel de azi. Lucrarea de faţă descrie două proiecte care au drept scop actualizarea infrastructurii de cercetare şi crearea de seturi de date care să susţină un nivel academic ridicat în cercetarea şi educaţia din silvicultură. Proiectul UPSMART 5.0 -- Actualizarea infrastructurii pentru cercetare, dezvoltare şi specializare inteligentă îşi propune dezvoltarea unor resurse de învăţare de ultimă generaţie care au drept scop asimilarea mai uşoară a modalităţilor de lucru cu tehnologie şi instrumente moderne. DIGIFOR -- Colectarea de date în format digital pentru un management forestier sustenabil îşi propune crearea unor baze de date digitale compuse din nori multi-temporali de puncte LiDAR şi fotografii pentru a susţinea activitatea de cercetare prin utilizarea de tehnologii moderne. Ambele proiecte sunt în desfăşurare şi au fost finanţate de către UEFISCDI. [ABSTRACT FROM AUTHOR]